Industrial facilities produce a variety of products and materials and can support processes such as petroleum refining, chemical processing, pharmaceutical production, and pulp and paper production. The process control system (e.g., Distributed Control System, Programmable Logic Controller, safety system, or supervisory control and data acquisition (SCADA) system) and measurement network employed includes a large number of field devices such as sensors and actuators which communicate with a control room.
Conventionally, field devices in a given industrial facility communicate over a process control loop with a control room and/or other field devices via wired connections. An example of a wired process communication protocol is known as the Highway Addressable Remote Transducer (HART) protocol. The HART Protocol makes use of the Bell 202 Frequency Shift Keying (FSK) standard to superimpose digital communication signals at a low level on top of a 4 to 20 mA analog signal. This enables two-way field communication to take place and makes it possible for additional information beyond just the normal process variable to be communicated to/from a smart field device.
HART communication is one of the most commonly used communication protocols used in the process industries. HART protocol is quite popular in safety systems and in most cases HART devices are connected either through serial/Internet Protocol (IP) HART multiplexers or going forward through FDI (Field Device Integration) communication servers (IEC 62769-Part 7 using Object Linking and Embedding (OLE) for process control (UPC) Unified Architecture (UA). With the advent of Industrial Interned of Things (HOT) it is also now possible for industrial facilities to access the Internet and to be accessed from Internet. Internet connectivity provides the ability to interact with the industrial facility from essentially any connected IP computer or computing device around the globe.
The industrial network may thus be susceptible to both internal and external cyber-attacks. As a preventive measure from external cyber-attacks, firewalls or other security measures may be taken to try to separate the industrial network from other networks.